Influence of y-irradiation on optical properties of GaSe crystals

Abstract

Performed in this work are low-temperature (T = 4.5K) investigations of exciton photoluminescence spectra in layered GaSe crystals both non-doped and doped with Zn and Sn in concentrations < 0.01 wt. %. The crystals were irradiated with y-quanta of the energy within the range 0 to 34 MeV with the doses up to 10^14 y/cm2. It has been shown that irradiation with the above doses results in improvement of quality in non-doped GaSe crystals: there disappears the “thin structure” of the emission line inherent to free excitons related with stacking fault defects of crystalline layers, observed is ordering the sets of bound exciton lines related with deep acceptors. As a consequence, there observed is an essential increase in the parameter S0 – integrated intensity of radiative recombination of free and bound excitons. Analogous changes related with healing of defects in GaSe crystalline lattice are observed after doping with Zn impurity. Irradiation of these crystals with y-quanta causes increasing S0, too. By contrast, doping with Sn impurity results in a sharp drop of S0 that begins to grow after irradiation with y-quanta. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/20899